From 77f256cda4b2f076f5169fdf1bc815f629eea361 Mon Sep 17 00:00:00 2001
From: "Alan D. Brunelle" <Alan.Brunelle@hp.com>
Date: Thu, 8 Nov 2007 08:34:44 -0500
Subject: [PATCH] Fixed REMAP to update Q2A & fixed #Q calculations

---
 btt/globals.h     |  2 +-
 btt/output.c      | 18 ++++++++++++++----
 btt/trace_queue.c |  1 +
 btt/trace_remap.c | 34 ++++++++++++++++++++++++----------
 4 files changed, 40 insertions(+), 15 deletions(-)

diff --git a/btt/globals.h b/btt/globals.h
index b4ef4e3..e1751e4 100644
--- a/btt/globals.h
+++ b/btt/globals.h
@@ -162,7 +162,7 @@ struct d_info {
 	FILE *d2c_ofp, *q2c_ofp;
 	struct avgs_info avgs;
 	struct stats stats, all_stats;
-	__u64 last_q, n_ds;
+	__u64 last_q, n_qs, n_ds;
 	__u32 device;
 
 	int pre_culling;
diff --git a/btt/output.c b/btt/output.c
index fd9392a..21392d6 100644
--- a/btt/output.c
+++ b/btt/output.c
@@ -141,15 +141,25 @@ void __output_dip_merge_ratio(struct d_info *dip, void *arg)
 {
 	double blks_avg;
 	char scratch[15];
-	double ratio, q2c_n = dip->avgs.q2c.n, d2c_n = dip->n_ds;
+	double ratio, q2c_n, d2c_n;
 
+	if (dip->n_qs == 0 || dip->n_ds == 0)
+		return;
+	else if (dip->n_qs < dip->n_ds)
+		dip->n_qs = dip->n_ds;
+
+	q2c_n = dip->n_qs;
+	d2c_n = dip->n_ds;
 	if (q2c_n > 0.0 && d2c_n > 0.0) {
-		ratio = q2c_n / d2c_n;
+		if (q2c_n < d2c_n)
+			ratio = 1.0;
+		else
+			ratio = q2c_n / d2c_n;
 		blks_avg = (double)dip->avgs.blks.total / d2c_n;
 		fprintf((FILE *)arg, 
 			"%10s | %8llu %8llu %7.1lf | %8llu %8llu %8llu %8llu\n",
 			make_dev_hdr(scratch, 15, dip),
-			(unsigned long long)dip->avgs.q2c.n,
+			(unsigned long long)dip->n_qs,
 			(unsigned long long)dip->n_ds,
 			ratio,
 			(unsigned long long)dip->avgs.blks.min,
@@ -162,7 +172,7 @@ void __output_dip_merge_ratio(struct d_info *dip, void *arg)
 			merge_data.blkmax = dip->avgs.blks.max;
 		}
 
-		merge_data.nq += dip->avgs.q2c.n;
+		merge_data.nq += dip->n_qs;
 		merge_data.nd += dip->n_ds;
 		merge_data.total += dip->avgs.blks.total;
 		if (dip->avgs.blks.min < merge_data.blkmin)
diff --git a/btt/trace_queue.c b/btt/trace_queue.c
index f882ad2..1d2afbe 100644
--- a/btt/trace_queue.c
+++ b/btt/trace_queue.c
@@ -32,6 +32,7 @@ static void handle_queue(struct io *q_iop)
 
 	q_iop->i_time = q_iop->gm_time = q_iop->d_time = (__u64)-1;
 	q_iop->is_getrq = -1;
+	q_iop->dip->n_qs++;
 }
 
 void trace_queue(struct io *q_iop)
diff --git a/btt/trace_remap.c b/btt/trace_remap.c
index 1e11ddc..22d340b 100644
--- a/btt/trace_remap.c
+++ b/btt/trace_remap.c
@@ -20,23 +20,37 @@
  */
 #include "globals.h"
 
-static void handle_remap(struct io *a_iop)
+static inline void cvt_pdu_remap(struct blk_io_trace_remap *rp)
 {
-	struct blk_io_trace_remap *rp = a_iop->pdu;
-	struct io *q_iop;
-
-	q_iop = dip_find_sec(a_iop->dip, IOP_Q, be64_to_cpu(rp->sector));
-	if (q_iop) 
-		update_q2a(q_iop, tdelta(q_iop->t.time, a_iop->t.time));
+	rp->device = be32_to_cpu(rp->device);
+	rp->device_from = be32_to_cpu(rp->device_from);
+	rp->sector = be64_to_cpu(rp->sector);
 }
 
+/*
+ * q_iop == volume device
+ * a_iop == underlying device
+ */
 void trace_remap(struct io *a_iop)
 {
+	struct io *q_iop;
+	struct d_info *q_dip;
 	struct blk_io_trace_remap *rp = a_iop->pdu;
 
-	a_iop->t.device = be32_to_cpu(rp->device_from);
-	if (io_setup(a_iop, IOP_A))
-		handle_remap(a_iop);
+	cvt_pdu_remap(rp);
+
+	a_iop->t.device = rp->device_from;
+	if (!io_setup(a_iop, IOP_A))
+		goto out;
+
+	q_dip = __dip_find(rp->device);
+	if (!q_dip)
+		goto out;
+
+	q_iop = dip_find_sec(q_dip, IOP_Q, rp->sector);
+	if (q_iop)
+		update_q2a(q_iop, tdelta(q_iop->t.time, a_iop->t.time));
 
+out:
 	io_release(a_iop);
 }
-- 
2.25.1